Nibbling machine



Nov. 2, 1937.

H, w. WILLIAMS NIBBLING MACHINE Filed Sept. 12, 1935 Harry Ill//////4V/// A1 His (Ittomeg desired shape of the part.

Patented Nov. 2, 1937 UNITED STATES PATENT OFFICE NIBBLIN G MACHINEApplication September 12, 1935, Serial No. 40,215

3 Claims.

This invention relates to nibbling machines and the like, and isparticularly directed to punches and dies for use in such machines.

There are several known types of nibbling machines used principally forroughing out irregularly shaped parts from flat material of the desiredthickness. These machines generally have a stationary die plate and anassociated reciprocating punch, which nibbles away superfluous materialto form the desired shaped part as said material is hand-fed into themachine.

There are two popular methods of obtaining the One is to outline theshape of the part on the surface of the material being used and theother, and probably the most popular method, is to use a template havingthe desired shape, said template being secured to the top surface of thematerial out of which the parts are to be made. In operation, theoutline is followed as closely as possible, or when a template is usedthe metal is nibbled away until the punch of the nibbling machinecontacts the edge of the template. The nibbling machine provides a meansfor quickly making experimental parts out of flat material, such partsbe ing used for example in adding machines, cash registers, typewritersand the like.

In one type of nibbling machine the front of the round punch is cut awayto form a cutting edge and a downwardly extending heel of said punchextends within the opening in the die to form a guide and support forsaid punch. This type of nibbling apparatus has proven unsatisfactorybecause the small cutting area of the punch quickly dulls when used uponcomparatively thick material and the excessive friction created betweenthe heel of the punch and the die when cutting thick material in acomparatively short time, galls said heel to such an extent that theefliciency of the nibbling apparatus is greatly impaired. Moreover the-heel of the punch, in cooperation with the opening in the die, does notform a sufficiently rigid support for the punch to prevent the cuttingedge thereof from coming into contact with the cutting edge of the die,thus further impairing the efliciency of the apparatus.

In another type of nibbling machine the entire circumference of theround nibbling punch forms a cutting edge, and this in itself materiallyincreases the efliciency of the apparatus by making it possible topresent work to the nibbling apparatus from any angle or direction andlikewise the increased. cutting surface of the punch prolongs the lifeof said punch and renders frequent sharpening thereof unnecessary.However, the advantages of this apparatus are overcome by failure toproperly support the lower end of the punch, whereupon the cutting ofthick material together with any looseness in the reciprocating headthat operates the nibbling punch springs said punch out of alinementwith the opening in the die and causes said punch to nibble on said dieand thus spoil the cutting edges of both punch and die.

The device comprising the instant invention includes a nibbling punch inwhich the entire circumference forms a cutting edge and naturallyembodies all the advantages outlinedabove. In addition means have beenprovided to rigidly support the lower end of the punch embodied in thepresent invention, so that accurate alinement of said punch with theopening in the nibbling die is maintained at all times regardless of thethickness of stock being cut or. regardless of looseness in thereciprocating head of the nibbling machine. Rigidly supporting the lowerend of the nibbling punch prevents said punch from springing out ofalinement with the opening in the die and thus materially prolongs thelife of the punch and die by making it unnecessary to sharpen or replacethem as often as is necessary in the types of devices outlined above.

It is therefore broadly an object of this invention to provide means toprolong the life and increase the efliciency of the punches and dies fornibbling machines. thereby decreasing the upkeep of such machines andimproving the quality of their work.

A more specific object is to provide means to maintain the punches ofnibbling machines in alinement with the openings in the dies, therebypreventing the dulling of the punches and dies, caused by the punchesbeing sprung into contact with the dies when cutting heavy material orcaused by looseness in the reciprocating head of the nibbling machines.

Another object is to provide means to support the lower end of thereciprocating punches for nibbling machines to maintain said punches inalinement with the openings in the dies to prevent dulling of thepunches and the dies and to obtain a better quality of work.

A further object is to supply means to rigidly support the punches ofnibbling machines against lateral thrust when cutting heavy material,said supporting means likewise adapted to maintain accurate alinement ofthe cutting surfaces of the punches and the openings in the dies at alltimes.

With these and incidental objects in view, the invention includescertain novel features of construction and combinations of parts, theessential elements of which are set forth in appended claims and apreferred form or embodiment .of which is hereinafter describedwith'reference to the drawing which accompanies and forms a part of thisspecification.

In the drawing:

Fig. 1 is a fragmentary front view, partially sectioned, of a typicalnibbling machine and illustrates the method of maintaining the nibblingpunch in-alinement with the opening in the die.

Fig. 2 is a plan view taken along line 2-2 (Fig. 1) looking in thedirection of the arrows, and shows in particular the nibbling die andits holder.

Fig. 3 is a plan view of thedle holder showing in particular the web orbridge that supports the lower end of the nibbling punch.

Description The present invention, which relates particularly to punchesand dies for nibbling machines may be embodied in any suitable type ofnibbling machine, one type of which is indicated by the referencenumeral In in Fig. 1. The nibbling machine has a head II whichvertically supports a reciprocating rod or ram l2, which may bereciprocated in any convenient manner to operate the punch of thenibbling machine. The lower end of the ram l2 has a boring adaptedto-receive the tenon of a punch holder or chuck H, which is secured inplace in the boring by means of a set screw i4 threaded in the ram l2. Acentral hole in the chuck I3 is adapted to I loosely receive a nibblingpunch l5, which is die holder 20 is secured on the top surface of atable 20 of the nibbling machine Ill.

. modate different thicknesses of material.

The lower end of the punch l5 terminates in a tenon or pilot 22, whichcooperates with the hole in a bushing 23 fast in a web or bridge 24which spans a hole'in the shoe 20, said hole registering with theopening I! in the die 19. Threads in the upper end of the hole in thechuck [3 in cooperation with the threaded upper end of said punchprovide a means of adjusting the cutting edge H5 in relation to the topsurface of the die plate I9. A set screw 25 threaded in the chuck l3retains the nibbling punch I! in adjusted position. I

Material to be shaped by the nibbling machine is advanced between thetop surface of the die I9 and the bottom surface of a guard or stripper-26 to the nibbling punch I5 Two symmetrical upwardly extending arms ofthe guard 26 are adjustably attached to the head ll of the nihblingmachine, thus providing ameans of adjusting the bottom surface of theguard in relation to the top surface of the die I9 to accom- It will benoted that the opening [1 in the die plate I9 is countersunk from thebottom surface of the die upwardly to within about one-half thethickness of said die. This is to provide clearance for the chips thataccumulate between the opening I! and the pilot 22 of the punch Ii asthe su-' perfluous metal is nibbied away. The chips drop through theopening in the holder 2. and through a similar opening in the table 2|,into a receptacle 21 removably attached to the bottom surface of thetable 2 I. It will be noted that a the pp r surface of the bridge 24 isA or wedgeshaped. to form inclined surfaces upon which it is impossiblefor the chips to accumulate.

Operation of the material when the ram I2 is in its highest position.While the machine is operating, sufficient pressure is placed upon thematerial, by

the operator, to maintain said material in contact with the pilot 22,which obviously determines the bite of the nibbling punch ii. The pilot22 in cooperation with the bushing 28 in the bridge 24 rigidly supportsthe lower end of the nibbling punch l5 and maintains the cutting edge I801' said punch in accurate alinement with the opening I! in the die is.

The advantages of supporting the nibbling punch in this manner arereadily seen and appreciated. For example, the resistance created whenshaping thick material is sometimes sufiicient to crowd or spring anunsupported punch out of alinement with the opening in the die, causingsaid punch to strike the die and ruin the cutting edges of both punchand die. Likewise, any looseness between the ram l2 and the head llpermits an improperly supported or an unsupported punch to be forced outof alinement with the opening in the die and results in the spoiling ordulling of the punch and die. Eupporting the-lower end of the nibblingpunch in the manner described above maintains the proper clearancebetween the punch and die at all times, thus making it possible tosatisfactorily shape much heavier material than is possible with anunsupported punch. Moreover, supporting the lower end of the punchcauses the nibbling apparatus to out clean without any pulling ortearing of the material being out, which improvesto a marked degree thequality of the work turned out by said apparatus.

It is obvious that the pilot 22 and the body of the punch l5 may beincreased or decreased in size respectively, to regulate the bite of thenibpling punch and to govern the strength of said pilot and punch inrelation to the thickness of the material being shaped.

The method of using a nibbling machine to shape pieces to the form of atemplate is generally as follows: A template having the outline of thepieces to be shaped is secured to the top surface of the material out ofwhich the pieces are to be made. The stripper 2B is then adjusted tofreely admit the template and the material between the top surface ofthe die l9 and the bottom surface of said stripper. Next the nibblingpunch 15 is adjusted in relation to the top surface of the die l9 sothat the cutting edge ii of said punch is above the top surface of thematerial out of which the parts are to be shaped but not above the topsurface of the template, when the ram I2 is in its highest position. Thematerial is' fed to the nibbling punch until the body or largestdiameter of the punch contacts the template. The template is thenmaintained in contact with the body of the punch while the superfluousmetal is nibbled away to form a part having the outline of the template.It is obvious regardless oi the direction from which the work ispresented to the punch.

2. In a nibbling machine of the character described, the combination ofa reciprocating punch 5 that a nibbling punch supported in the mannerhaving a circular cutting edge to which material 5 described above hasmany advantages over an may be presented from any angle; a die havingunsupported nibbling punch, and it is believed an opening to receive thepunch; a holder for the that these advantages will be realized from thedie, said holder having an opening that registers foregoingspecification. with the opening in the die; aweb spanning the While theform of mechanism herein shown opening in the holder; and a work feedguiding 10 and described is admirably adapted to fulfill the pilotintegral with the punch and extending objects primarily stated, it is tobe understood downwardly from the cutting edge thereof into an that itis not intended to confine the convention opening in the web to maintainthe punch in to the one form or embodiment h'erein disclosed, alinementwith the die at all times irrespective for it is susceptible ofembodiment in various oi the thickness of the material being cut and 15-forms all coming within the scope of the claims irrespective of theangle from which the material which follow. is presented to the punch.

What is claimed is: 3. In a machine of the class described, the 1. In anibbling machine of the character decombination of a reciprocating punchhaving a scribed, the combination of areciprocating punch cutting edgeon all sides thereof to which ma- 20 having .a cutting edge on all sidesthereof to terial may be fed from any direction, a die havwhich work maybe presented from any direction; ing an opening cooperable with thepunch, a work a work feed limiting pilot integral with the punch feedlimiting means integral with said punch and and adjacent the cuttingedge thereof; a die havoperable to limit the feed of work when it is feding an opening to receive the punch; a holder for from any direction,said work feeding means ex- 25 the die, said holder having an openingregistering tending downwardly into the opening in the die, with theopening in the die; and a web within and means mounted below the die andcooperable the opening in the holder, said web having a guidwith saidwork feed limiting means to prevent ing surface cooperating with thework feed limlateral displacement of the punch in any direcao itingpilot to maintain the cutting edge of the tion.

punch in alinement with the opening in the die Patent No. 2 ,098,022.

HARRY W. WILLIAMS.

HARRY W. WILLIAMS.

November 2 1937 It is hereby certified-that error appears in the printedspecification of the above numbered patent requiring correction asfollows column, line 15, 011111112, after the word ."web" insert'tocontrol the work feed and; and that the said Letters Patent should beread with this correction therein that the samemay conform to the recordof the case in the Patent Office.

Signed and sealed this 1st day of February, A. D- 1958.

Page 3, second Henry Van -Arsdale, Acting Commissioner of Patents.

(Seal) the template. The template is then maintained in contact with thebody of the punch while the superfluous metal is nibbled away to form apart having the outline of the template. It is obvious regardless oi thedirection from which the work is presented to the punch.

2. In a nibbling machine of the character described, the combination ofa reciprocating punch 5 that a nibbling punch supported in the mannerhaving a circular cutting edge to which material 5 described above hasmany advantages over an may be presented from any angle; a die havingunsupported nibbling punch, and it is believed an opening to receive thepunch; a holder for the that these advantages will be realized from thedie, said holder having an opening that registers foregoingspecification. with the opening in the die; aweb spanning the While theform of mechanism herein shown opening in the holder; and a work feedguiding 10 and described is admirably adapted to fulfill the pilotintegral with the punch and extending objects primarily stated, it is tobe understood downwardly from the cutting edge thereof into an that itis not intended to confine the convention opening in the web to maintainthe punch in to the one form or embodiment h'erein disclosed, alinementwith the die at all times irrespective for it is susceptible ofembodiment in various oi the thickness of the material being cut and 15-forms all coming within the scope of the claims irrespective of theangle from which the material which follow. is presented to the punch.

What is claimed is: 3. In a machine of the class described, the 1. In anibbling machine of the character decombination of a reciprocating punchhaving a scribed, the combination of areciprocating punch cutting edgeon all sides thereof to which ma- 20 having .a cutting edge on all sidesthereof to terial may be fed from any direction, a die havwhich work maybe presented from any direction; ing an opening cooperable with thepunch, a work a work feed limiting pilot integral with the punch feedlimiting means integral with said punch and and adjacent the cuttingedge thereof; a die havoperable to limit the feed of work when it is feding an opening to receive the punch; a holder for from any direction,said work feeding means ex- 25 the die, said holder having an openingregistering tending downwardly into the opening in the die, with theopening in the die; and a web within and means mounted below the die andcooperable the opening in the holder, said web having a guidwith saidwork feed limiting means to prevent ing surface cooperating with thework feed limlateral displacement of the punch in any direcao itingpilot to maintain the cutting edge of the tion.

punch in alinement with the opening in the die Patent No. 2 ,098,022.

HARRY W. WILLIAMS.

HARRY W. WILLIAMS.

November 2 1937 It is hereby certified-that error appears in the printedspecification of the above numbered patent requiring correction asfollows column, line 15, 011111112, after the word ."web" insert'tocontrol the work feed and; and that the said Letters Patent should beread with this correction therein that the samemay conform to the recordof the case in the Patent Office.

Signed and sealed this 1st day of February, A. D- 1958.

Page 3, second Henry Van -Arsdale, Acting Commissioner of Patents.

(Seal)

